1. Field of the Invention
The present invention relates to an image processing apparatus, an image processing method, and a recording medium storing a program thereof for generating image data to print a color chart made up of a plurality of color patches on a print medium, entering identification information of a color patch selected to represent a color that is closest to a designated color from the color chart printed based on the image data, and making a color adjustment of a print based on such identification information.
2. Description of the Related Art
With significant advances in inkjet technology in recent years, it has become possible for inkjet printers to produce large color prints of high quality at high speeds. Inkjet printers are not only popular for private or home use, but nowadays also are widely used in commercial applications. Inkjet printers make it possible to print on POP (point of purchase) posters, wall posters, large-size mediums such as outdoor advertisements and billboards, roll mediums, and thick hard mediums.
There are a wide variety of print mediums (hereinafter also referred to as “mediums”) available for use in prints to meet various commercial demands. For example, such print mediums include paper mediums, such as synthetic paper, thick paper, aluminum-evaporated paper, etc., resin mediums such as those made of vinyl chloride, PET, etc., and tarpaulin paper made of woven fiber cloth with synthetic resin films applied to both surfaces thereof.
Since advertisement prints are expected to be effective to arouse consumers' motivation to buy advertised products through visual sensations of the consumer, the color finish of such prints is of particular importance. Heretofore, there have been disclosed various color matching technologies, such as a method of generating an ICC (International Color Consortium) profile, a method of adjusting a designated color, etc., as a print color managing means. Such color matching technologies are applicable not only to inkjet printers but also to all types of digital printers, including those based on electrophotographic and thermosensitive principles, together with their peripheral devices across the board.
The method of adjusting a designated color referred to above comprises a method of making fine color adjustments of an area of interest in an image in order to bring the color into substantial conformity with a given color (designated color) designated by a color sample of color chips, while maintaining the color balance of the image as a whole. There have been disclosed various methods of adjusting a designated color.
For example, Japanese Laid-Open Patent Publication No. 2000-217007 discloses a method of bringing the impression of a designated color displayed on a display device and the impression of a color printed by a printing machine into conformity with each other. Specifically, Japanese Laid-Open Patent Publication No. 2000-217007 discloses a display window displayed on the display device, in which the displayed color is changeable, and a printed color chart of 27 colors, which are thought to be close to a designated color that is displayed (see FIGS. 4 and 5 of Japanese Laid-Open Patent Publication No. 2000-217007).
The operator sets a designated color that is to be displayed in the display window, presses a print button to print the color chart on the printing machine, selects one of the 27 colors of the color chart, which is closest to the designated color, and enters the number of the closest color into the display device, for thereby strictly approximating the impression of the designated color displayed in the display window by the impression of the color printed on the printing machine.
The 14th color at the center of the color chart of 27 colors represents a color of C, M, Y values that corresponds to the designated color, whereas the other colors of the color chart have C, M, Y components that are slightly different from each other by small quantities ΔC, ΔM, ΔY (see FIG. 7 of Japanese Laid-Open Patent Publication No. 2000-217007).
A color range that can be reproduced by a printing machine is known as a gamut, which is defined depending on the colors and number of inks that are used by the printing machine in order to produce color images.
If the printing machine carries inks of colors C, M, Y, K (so-called process colors), but not optional inks of a designated color and similar colors, then the printing machine is required to reproduce the designated color based on a combination of the colors C, M, Y, K. A color matching process using a profile often fails to match the designated color efficiently.
For example, if the operator does not recognize that the designated color is a color outside of the gamut, then the operator searches in vain for a color patch, which is of the same color as the designated color, by repeating a process of printing and visually checking the color chart.
If the designated color falls within the gamut, but is near to the boundary thereof, then since it is difficult to predict printed colors with respect to C, M, Y, K values, the operator needs to be highly skilled and have many years of experience. If the operator is not skilled and experienced enough to perform such color adjustments, then it is tedious and time-consuming to match the designated color, and possibly an optimum color will not be selected.
According to the method disclosed in Japanese Laid-Open Patent Publication No. 2000-217007, if the designated color falls outside of the gamut, or falls within the gamut but is near the boundary thereof, then it takes a long period of time to adjust the designated color.